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PlantSpace P&ID Engineering Overview

By Joe Smetona, PlantSpace Technical Analyst
Bentley Corporate Office

P&IDs—“Piping and Instrumentation Diagrams”—have always been at the pinnacle of the plant engineering and design process. They provide the foundation for design work in new plant construction and in the modernization of older plants. The advent of the JSpace Object Engine used in Bentley’s PlantSpace P&ID software has revolutionized the process of generating engineering changes and has enabled database reporting immediately after processing the design file.

PlantSpace P&ID uses the Object Engine to generate a separate “Object Model” file that contains all the components of the P&ID, as well as groups these components together in a logical format. This results in an “intelligent” P&ID design that can easily be queried or manipulated (see Figure 1). The independence of the DGN file from the JSpace generated Object Model file (JSM) helps to maintain the stability of a project. This is in stark contrast to other “dynamic” systems, which rely on a much higher level of database connectivity during the drafting process. This continuous connectivity can cause problems and eventually hamper production.

Figure 1
Figure 1: A typical P&ID work session in PlantSpace P&ID
Figure 2
Figure 2: PlantSpace P&ID Conformance Tool.
Figure 3
Figure 3: PlantSpace P&ID Processing Commands dialog box.

Many process plants built during the 1960s and 1970s utilize relay logic, often accompanied by Tenor Drum Controllers, to control their processes. These are extremely reliable means of control, but require elaborate control rooms with level and temperature indicators, controllers, alarms, etc. Modernization of these plants, along with the need to improve productivity, is often required in order to remain competitive in today’s market. By retrofitting with Distributed Control Systems (DCS) or Programmable Logic Controllers (PLC), programmable precision is applied to process control, and many tasks are automated. Plants that have installed these newer types of controls remove the control panel instruments and switches altogether. The creation of wiring diagrams; elementary, logic, loop and terminal block diagrams; as well as FTA module and arrangement drawings required for these retrofits are all contingent on the P&ID master document. In addition, the P&ID’s for this massive conversion are constantly in flux.

One of the most difficult tasks in this process is creating and updating an I/O list for connection of the new plant computer system to the entire plant. To help address this, drawings created using PlantSpace P&ID can provide a variety of reports in short order using the most popular database formats. Doing so can provide the Project Engineer with the foundation for the I/O list, as well as which computer points are used for which valve actuators, motor control centers, temperature elements, limit switches, etc. This process is cyclic, and any improvement in turnaround time affects many engineering/design areas and, ultimately, the project completion date.

Figure 4
Figure 4: JSpace Class Editor dialog box.
Figure 5
Figure 5: PlantSpace Object Engine dialog box.
The impetus for using PlantSpace P&ID with the JSpace Object Model is also reinforced by various external factors: The existing plant may have years of modifications with no as-built drawings produced, require extensive walk-downs, missing documentation of terminal block wiring or have scheduled demolition.

While PlantSpace P&ID can be used for the creation of new documents, drawings created on other CAD systems can also be converted to work with PlantSpace P&ID through use of built-in conformance tools. Additional symbols can be created for unique equipment, and symbols can be added to existing classes. Since PlantSpace P&ID uses the standard MicroStation design file format, files created in other programs can be imported using MicroStation's DWG and DXF translators. Once converted, the existing geometry can be adjusted to the proper settings by using the PlantSpace P&ID Conformance Tools (see Figure 2).

New construction, particularly in Photo Film/Paper production or Pharmaceutical, places extraordinary demands on P&ID production. These industries utilize highly specialized equipment and processes, and may also utilize computer controlled multi-port valves that can require specialized coding or symbology. Even in new construction, constant change of the P&ID design is still present. PlantSpace P&ID can be customized to handle these complexities, and yet the design file remains independent of the Object Model file, providing excellent reliability with day-to-day revisions. Symbology addressing the I/O points is now in place on the P&ID allowing the Object Engine to utilize this information in processing. Keeping up with the I/O list is also less problematic, because other factors are under control and repetitive changes can be quickly incorporated (and processed) in the P&IDs. The Object Model file created from processing is used for all reporting functions and as always remains independent of the original design file.

Processing commands and rules can be customized to accommodate stages of a typical project such as Conceptual Design, Detailed Design, Construction, Start-up, Operations and Maintenance (see Figure 3). New construction using the Object Engine approach will pave the way for easier plant updates in the future.

PlantSpace P&ID has many levels of customization available to the user. The default installation provides base coverage for most general applications, utilizing common classes for valves, equipment, fittings, line breaks, pipe, flow instruments and text parameters. Editing class libraries using the JSpace Class Editor (Figure 4) or Processing Command files with the PlantSpace Object Engine (Figure 5) allows an unprecedented amount of control in the resulting JSpace Object Model files. Using these methods to customize a project will provide the full benefit of this dynamic program.

Although general in scope, the information contained above may provide insight into the importance of the P&ID document and the manner in which PlantSpace P&ID addresses this. The methodology illustrated provides for the creation of independent object model files for all reporting and querying functions, and yet still allows the P&ID to retain “intelligence” well beyond that of a simple CAD file.

PlantSpace P&ID User and Customization courses are also available from Bentley. Please refer to http://bentleyinstitute.bentley.com/ps/schedule.htm for further training information.

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